Christopher has taken 6 exams and his average score so far is 84. If he gets 100, a perfect score, on the remaining 2 exams, what will his new average be?
Solution: If he gets 100 on the remaining exams, the sum of his scores will be $6 \cdot 84 + 2 \cdot 100 = 704$ His overall average will then be $704 \div 8 = 88$.